Laurel Wilt Avocado (Stump or Remove)

[fruitmonger]

After 8+ years of surviving Laurel Wilt and producing fruit relatively undisturbed my lone Monroe tree has finally succumb to the effects of this disease.

About 3 years ago the tree sustained a rather significant die off of many stems which were quickly trimmed off.

This trimming seemed to stimulate new growth and the tree came back relatively strong in vegetative growth.

Fruit production was looking pretty good for this past season but all of a sudden after fruit set the tree again had some wilting and all but a scant few fruit aborted.

Those fruit that held matured and the matured fruit were very tasty...ot many but delicious.

A few weeks ago I noticed that the tree was now showing marked die off in most branches and all but two branches off of the main trunk and a sucker coming out of tree base were toast.

I decided to stump the tree and just wait and see what happens.

I feel torn...as if my decision to keep this tree is putting other trees in the neighborhood in jeopardy.

To tell the truth I am not super attached to the tree but removing it seems like a giant pain in the ass.

My yard is solidly packed limestone fill about 2-3" below the top soil....there are pockets of dirt but taking it out and breaking it up to remove the infected roots sound about as fun as a root canal without anesthesia.

I hear many folks are opting to stump vs remove to see if the tree has enough vigor and healthy tissue to establish new moisture and nutrient flow to new limbs that can replace what was lost.

The tree has managed to do just that several times....again....not sure this is a responsible thing to continue to do.

Anyone's thought on this are welcome.   

I am attaching a few images...

[pineislander]

Stump remover is supposed to work.
https://www.youtube.com/watch?v=tnL_depDcfg

[CTMIAMI]

Stumping the trees is not a good choice, especially if there are avocados in the area. Is like letting a Troyan Horse into your grove. The roots continue to spread the fungus while the tree is re-growing new vegetation on the new xylem growing (giving you the illusion that all is well) only to eventually die again by then it has spread to adjacent trees.  My grove still operational because I remove any contaminated tree right away. Roots and all.

[CTMIAMI]

By the way, I would not replant avocado in the area for 24 months to be safe.

[fruitmonger]

My grove still operational because I remove any contaminated tree right away. Roots and all.

First let me thank you Carlos and pineislander for your replies and advise.

I expected the consensus would be to remove and so I will because it really is the right thing to do to try and control the spread of this to any degree that we can.

Thanks again

[JakeFruit]

I would follow Carlos' advice, but if you can't for some reason, Epsom Salt will help speed up the breaking down process. To do that, take it down as low as possible, drill holes spaced ~6"-8" apart with as large a bit as you have & as deep as you can go straight down into the stump, then fill each hole with ES and then pour hot water in the holes. Covering the stump with mulch/organic matter and watering it occasionally will also increase the speed of decomposition. Adding a (black) over the top of everything will increase the soil temperature and help retain moisture.




ES is not actually a salt, it's magnesium sulfate and beneficial to plants/soil. The amount you use is probably too much of a good thing (from what I read, too much magnesium inhibits calcium uptake), so I wouldn't be in a rush to plant another tree there right away.

[CTMIAMI]

Fruitmonger do what is economically feasible to you. There are literally 1000's of infected trees in Florida, not only avocados but sassafras, red bay etc. The simplest thing would be to cut the tree close to the ground and find some inexpensive way to remove or treat the root. 

[fruitmonger]

Update.  I stumped the tree and left it to its own devices.

Here is how it looks today.  Maybe some fruit next year.

Though some folks might want to see.

[ScottR]

Why have you let tree regrow when removing was best option and you seemed to agree?? Did you learn something new you haven't share like was not 'Laurel Wilt' or??

[pagnr]

ES is not actually a salt, it's magnesium sulfate and beneficial to plants/soil. The amount you use is probably too much of a good thing

Just a small point, it is a nutrient as you say, but it behaves as a salt with an EC.
If NaCl is salt, KCl and CaCl also behave as salts, as does MgCl, MgSO4 ( magnesium sulphate ), and all similar structured compounds.
If you use these nutrients excessively, or make very strong liquid fertiliser solutions, the EC ( salt effect ) will be very high.
The advantage of MgSO4 to NaCl in tree removal is probably that the MgSo4 will eventually be utilised as a nutrient, whereas the NaCl is required in far smaller amounts, and has well known negative effects if out of balance.( ie salinity )

[fruitmonger]

Why have you let tree regrow when removing was best option and you seemed to agree?? Did you learn something new you haven't share like was not 'Laurel Wilt' or??

Because while removing it is probably the best thing I could have done it takes lots of time and effort.

I am on solid limestone and getting something out of the ground is not just a matter of digging.

It takes machinery and manpower....a jackhammer and some help.

So i stumped it and then left it alone....and it grew back.

[JakeFruit]

ES is not actually a salt, it's magnesium sulfate and beneficial to plants/soil. The amount you use is probably too much of a good thing

Just a small point, it is a nutrient as you say, but it behaves as a salt with an EC.
If NaCl is salt, KCl and CaCl also behave as salts, as does MgCl, MgSO4 ( magnesium sulphate ), and all similar structured compounds.
If you use these nutrients excessively, or make very strong liquid fertiliser solutions, the EC ( salt effect ) will be very high.
The advantage of MgSO4 to NaCl in tree removal is probably that the MgSo4 will eventually be utilised as a nutrient, whereas the NaCl is required in far smaller amounts, and has well known negative effects if out of balance.( ie salinity )

I'll agree with whatever you said, anybody that knows even portions of the periodic table beats me....I sucked in science class.
From what I read, ES draws moisture out of any plant matter it comes in contact with, so the ES leaching down into the still live/viable root system of a recently stumped tree dries it out and speeds the process of rotting.

[palmcity]

So i stumped it and then left it alone....and it grew back.

10.8.22 has some suggestions to try for those wanting to try to help protect a avocado tree... Very interesting ideas. I might quote a few, but here is the link: 
https://www.floridatoday.com/story/life/2022/10/08/take-measures-prevent-laurel-wilt-avocado-trees/8175366001/

"There are things that can be done to help the tree grow healthy and therefore not be a susceptible host for the laurel wilt fungus.

The most important step to take is to get the mycorrhizae back into the soil to help support the tree. All trees are considered mycorrhizal dependent, so don’t grow your trees without them. Email me at sasc@ufl.edu if you don’t know how to get the biology established around the root systems of your trees, lawn, ornamental plants and everything else you want to grow in your yard.

Fertilizing correctly is also important, and that begins with a soil test. If you are interested in that I can also email you a copy of our soil testing form. It takes time for the soil food web to get established, so identifying low levels of any nutrients will be easy to correct.

To produce nutritious avocados, it is also beneficial to re-mineralize the soil with trace elements from a volcanic source, at least while the soil food web is getting established.

Another beneficial practice for the tree would be to spray the foliage with a liquid seaweed spray. This is a simple way to provide trace elements and growth hormones directly to the foliage of the tree, for translocation throughout the entire canopy. Spraying weekly will provide the most benefit.

One last thing you can do to help boost your tree’s defenses against the fungus would be to add aspirin to the liquid seaweed solution and spray them on the foliage together.  Research at the University of Rhode Island found that spraying a plant’s foliage with salicylic acid from aspirin results in a Systemic Acquired Resistance in the plant, which can help the plant protect itself from insects and diseases.

In the research, ¾ of an aspirin was dissolved in water and sprayed on the foliage of plants. It may be easier to dissolve 3 chewable baby aspirin, in a small amount of hot water, add that to enough cold water to make a gallon, and add the liquid seaweed to spray them together."

A few new ideas like the Aspirin addition, at least for me.

[CTMIAMI]

I'm wondering, if there is  research to back up the statement below from the article any documentation that offers any protection from Laurel Wilt?

The most important step to take is to get the mycorrhizae back into the soil to help support the tree. All trees are considered mycorrhizal dependent, so don’t grow your trees without them. Email me at The most important step to take is to get the mycorrhizae back into the soil to help support the tree. All trees are considered mycorrhizal dependent, so don’t grow your trees without them. Email me at sasc@ufl.edu if you don’t know how to get the biology established around the root systems of your trees, lawn, ornamental plants and everything else you want to grow in your yard. if you don’t know how to get the biology established around the root systems of your trees, lawn, ornamental plants and everything else you want to grow in your yard.